1. Field of the Invention
The present invention relates to a liquid discharge head substrate, a liquid discharge head, and a printing apparatus.
2. Description of the Related Art
Japanese Patent Laid-Open No. 2010-155452 describes a liquid discharge head substrate that suppresses the influence of the voltage variation of a power supply line which supplies power to a discharge element for discharging a liquid. In this liquid discharge head substrate, transistors are connected to the two terminals of the discharge element. These transistors control a voltage and a current applied to the discharge element. This makes it possible to stably supply power to the discharge element.